1. Field of the Invention
The present invention relates to a flying type paper pasting device to be employed in a paper feeding portion of a rotary press continuously supplying a paper web, which pasting device is provided with an adhering portion for pasting papers by an adhesive double coated tape, and a web paper take-up body placed at a stand-by state in a condition where an end of paper is temporarily adhered on a peripheral surface is driven to rotate at a peripheral speed substantially equal to a currently consumed paper being fed, for pasting paper by depressing the currently consumed paper on to the end of the paper on the roll of paper being driven to rotate by means of a depressing member.
2. Description of the Related Art
A prior art of a paper pasting device of the type, to which the present invention concerns, has been disclosed in Japanese Examined Patent Publication No. Hei 6-71954. In the paper pasting device disclosed in the above-identified publication, a support shaft is rotatably supported between frames of a paster arm portion of the paper pasting device. On the support shaft, a depressing member is integrally secured for rotation therewith. On the support shaft, a spring for causing quick movement of the depressing member toward the currently consumed paper, is mounted.
On the other hand, on the support shaft, an arm is mounted with integrally securing one end thereof. The other end of the arm is connected to a rod of an air cylinder connected on the side of the frame of a paster arm portion
On the other hand, in order to maintain the depression member in the stand-by state within the paster arm portion against a spring force, a stopper preventing the support shaft from rotating, is provided on a frame surface of the paster arm. The stopper is actuated by a solenoid. When the solenoid is actuated in response to a command from a control unit, rotation of the support shaft is permitted.
Then, the support shaft is quickly rotated by a force of the spring. The depressing member fixed on the support shaft is moved toward the currently consumed paper.
Subsequently, an electromagnetic switching valve disposed in the air cylinder is switched in response to the command from the control unit to actuate the air cylinder for driving the depressing member fixed on the support shaft in a direction toward the currently consumed paper.
With the construction set forth above, on the basis of a timing control of the control unit, the solenoid is actuated and thus, the stopper permits rotation of the support shaft. Then the depressing member is abruptly moved toward the currently consumed paper by the force of the spring for depressing the currently consumed paper onto the roll of paper driven to rotate at substantially the same peripheral speed as the currently consumed paper. Upon depression, a reaction force from the roll of paper acts on the depression member to cause bounding of the depressing member.
However, upon occurrence of the reaction force, the air cylinder is actuated. Against this reaction force, depressing force of the depressing member is applied for restricting bounding of the depressing member so that pasting of the paper web can be performed without causing delay of timing.
However, in the prior art set forth above, the depressing body is integrally fixed on the support shaft which is driven to cause angular displacement by the spring, and the arm connected to a rod of the air cylinder in order to restrict bounding of the depressing member is also integrally fixed to the support shaft.
Accordingly when the solenoid is actuated by the control unit to release the stopper to pivotally move the depressing member toward the currently consumed paper according to angular displacement of the support shaft by a spring force exerted by the spring, the arm connected to the rod of the air cylinder is integrally moved and the rod of the air cylinder is also moved.
Therefore, at this time, a friction force at the contacting portion between a piston of the air cylinder and the rod and the rod cover serves as a resistance against movement of the depressing member by the spring to cause difficulty in depressing of the currently consumed paper onto the roll of paper being driven to rotate, at a desired timing and thus to possibly cause failure of pasting of paper.
In order to restrict bounding of the depressing member, the air cylinder and the control unit or so forth for actuating the air cylinder are provided to make the device complicated.